Causes of Muscle Spasms

A muscle spasm occurs when a muscle contracts involuntarily. Muscle spasms often occur spontaneously with no stimulation. If stimulation is the cause, it is most often trivial. Muscle spasms tend to last for several minutes and will cause pain before they slowly ease. They can affect any muscle, but they most commonly affect the muscles in the hands, feet and calves. Muscle spasms can be caused by a number of things such as dehydration, prolonged exercise, certain metabolic disorders, myotonia, and muscular or neurological diseases. While muscle spasms are common symptoms of many different diseases and conditions, not all muscle spasms indicate a problem.

Prolonged Exercise

• Prolonged exercise can cause muscle spasms. When you exercise for long periods of time without taking breaks, severe energy depletion may result and this leads to the muscles not being able to relax. When a muscle cannot relax, a muscle spasm occurs.

Dehydration

• Dehydration is a loss of fluids as well as salts, and it can cause muscle spasms. Salts include sodium, calcium, magnesium and potassium. When fluid and salt loss occurs, ion balances in the nerves and muscles can become disrupted. When they are disrupted, the nerves and muscles are prevented from recovering and responding normally, so a muscle spasm occurs.

Metabolic Disorders

• Certain metabolic disorders that cause muscle enzyme deficiencies can cause muscle spasms. When there is a muscle enzyme deficiency, the energy supply within a muscle is affected and muscles do not work properly. This can lead to muscle spasms.

Myotonia

• Myotonia does not cause spontaneous muscle spasms, but many people with this condition do experience muscle spasms after exercise. People with myotonia often experience more muscle spasms when it is cold.

Muscular and Neurological Diseases

• Certain muscular and neurological diseases can cause muscle spasms. Muscular diseases can cause muscle spasms because of damaged muscle, and neurological diseases can cause muscle spasms because of damaged nerves. Common muscular and neurological diseases that can cause muscle spasms include fibromyalgia and multiple sclerosis.

Other Causes

• Many other things can cause muscle spasms. Certain medications, alcohol abuse, pregnancy, muscle fatigue, kidney failure and hypothyroidism all can cause muscle spasms. Other causes include cold temperatures, nerve damage, fatigue and neurodegenerative disease. And, some people will just experience mild, brief muscle spasms from time to time without any underlying cause.